─────── § 04. NPA RECORD · 857 · FOLIO 0659 OF 0801 ──────────────
857
United States NPA Record
Overlay area code introduced in May 2001 to relieve area code 617 in the Boston metropolitan area, requiring 10-digit dialing.
Overlay area code introduced in May 2001 to relieve area code 617 in the Boston metropolitan area, requiring 10-digit dialing.
IN SERVICEFirst record · 2001
§ 04.05Event Summary
other · 1service expansion · 1
§ 04.06
Documentary Record · 3 events
CHRONOLOGICAL ORDER
2001-05-02
NPA 857 overlay introduced on 617
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2025-10-01
other
617/857 NPA projected exhaust by 2059
As of October 2025, the 617/857 overlay complex is projected to be exhausted by the year 2059, according to NANPA exhaust analysis.
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2025-10-01
service expansion
617/857 NPA projected exhaust by 2059
The 617/857 overlay complex is projected to exhaust its available numbering resources by the year 2059, according to the October 2025 NPA Exhaust Analysis.
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